Sweetpotato plant named &#39;Evangeline&#39;

ABSTRACT

A new variety of sweetpotato identified as ‘Evangeline’ is disclosed having disease resistance to both southern root-knot nematode and soil rot, a deep orange flesh, a high sucrose content, and high yield characteristics.

This invention pertains to a new and distinct variety of sweetpotato.

BACKGROUND OF THE INVENTION

Sweetpotatoes, unlike Irish potatoes (Solanum tuberosum), are not tuberpropagated plants. A “tuber” is a short, thickened portion of anunderground branch. Along a tuber “eyes” are found, each of whichcomprises a ridge bearing a scale-like leaf (analogous to a branch leaf)having minute meristematic buds in the axial of the leaf. By contrast,sweetpotato roots are developmentally and anatomically true roots,lacking meristematic buds, and are not derived from an undergroundbranch. Sweetpotatoes do not form tubers.

SUMMARY OF THE INVENTION

Genus And Species Name

This new and distinct sweetpotato variety, Ipomoea batatas (L.) Lam.,demonstrates superior disease resistance to southern root-knot nematode,and exhibits a deep orange flesh and a higher sucrose content comparedto the ‘Beauregard’ variety. It also demonstrates a resistance to soilrot and high yield characteristics similar to ‘Beauregard.’

Variety Denomination

This new and distinct sweetpotato variety is identified as ‘Evangeline’,and is characterized by its dark orange flesh, elliptical roots, andhigher sucrose content.

BRIEF DESCRIPTION OF THE DRAWINGS

The file of this patent contains at least one photograph executed incolor. Copies of this patent or patent application with color drawing(s)will be provided by the Patent and Trademark Office upon request andpayment of the necessary fee.

FIG. 1 is a color photograph of the fleshy root form of the novelvariety of sweetpotato identified as ‘Evangeline’.

FIG. 2 is a color photograph of the fleshy root form of the sweetpotatovariety identified as ‘Beauregard’.

FIG. 3 is a color photograph of the canopy biomasses of the novelvariety of sweetpotato identified as ‘Evangeline’ (shown on the leftside of the photograph) and the variety identified as ‘Beauregard’(shown on the right side of the photograph).

DETAILED BOTANICAL DESCRIPTION

This new variety of sweetpotato, named ‘Evangeline’, resulted from anopen pollinated cross performed in 1998 to the Louisiana AgriculturalExperiment Station female parent ‘L94-96’ (‘Bienville’ patented U.S.Plant Pat. No. 15,380 P3). The male parent was unknown. One patentedmale parent (‘L96- 117’ U.S. Plant Pat. No. 15,038 P2) was among thepotential pollen sources in the crossing nursery. Both patents were heldby the Louisiana Agricultural Experiment Station in Baton Rouge, La.‘Evangeline’ was developed by the Louisiana Agricultural ExperimentStation in Baton Rouge, La., to provide a variety with characteristicssimilar to ‘Beauregard’ (unpatented), but with improved resistance tosouthern root-knot nematode and higher sucrose content. ‘Evangeline’ wascharacterized by a darker orange flesh. The female parent ‘Bienville’had similar disease resistant characteristics to that of ‘Evangeline’.

Plants of ‘Evangeline’ and ‘Bienville’ can be distinguished by lightergreen vines [2.5 (green) Y (yellow) 5/6] for ‘Evangeline’ versus greenvines [7.5 G (green)Y (yellow) (5/6)] for ‘Bienville’. Color terminologyused herein is in accordance with the Munsell® Book of Color (MunsellColor, GretagMacbeth LLC, 617 Little Britain Road, New Windsor, N.Y.12553-6148). The color descriptions and color illustrations are asnearly true as is reasonably possible. However, it is understood thatboth color and other phenotypic expressions described herein may varyfrom plant to plant with differences in growth, environment and culturalconditions, without any change in the genotype of the variety‘Evangeline’.

‘Evangeline’ roots were stored during the winter at the LouisianaAgricultural Experiment Station (Sweetpotato Research Station) in Chase,La. ‘Evangeline’ was planted the following spring, resulting inapproximately 8-10 sprouts per root. Cuttings from the sprouts weretransplanted successfully for asexual reproduction. Asexual propagationof the new cultivar by cuttings has shown that the unique features ofthis new sweetpotato were stable and that the plant reproduced true totype in successive generations of asexual propagation. Plants describedherein were approximately 90-110 days in age from planting in full sunfield plantings.

FIG. 1 depicts the fleshy root form of the ‘Evangeline’ sweetpotato. Theskins vary in color from light to medium rose, which is similar to‘Beauregard’, both at harvest and after several months of storage asshown in Table 1. Munsell® Book of Color values for skin and flesh forboth ‘Evangeline’ and ‘Beauregard’ storage roots at harvest are shown inTable 1. The ‘Beauregard’ sweetpotato is depicted in FIG. 2. The skinfor both ‘Evangeline’ and ‘Beauregard’ was smooth. ‘Evangeline’ storageroots were elliptical without lobing, and they were not as long as‘Beauregard’. The ‘Evangeline’ cortex was 4-5 mm in depth. TABLE 1Variable Variety Color Skin ‘Evangeline’ 7.5 R (red) 5/6 ‘Beauregard’7.5 R (red) 5/6 Flesh ‘Evangeline’ 2.5 Y (yellow) R (red) 7/12‘Beauregard’ 2.5 Y (yellow) R (red) 7/10

FIG. 3 depicts the canopy biomass of both ‘Evangeline’ sweetpotatoes and‘Beauregard’ sweetpotatoes. ‘Evangeline’ has green-stemmed vines [2.5 G(green) Y (yellow) (5/6)] from the apex to the crown of the roots. The‘Evangeline’ canopy biomass appears to be greater than that for‘Beauregard’. The ‘Evangeline’ canopy architecture was upright (30 cm inheight from the soil surface) and erect prior to spreading (80 cmradius), while ‘Beauregard’ exhibited a prostrate growth habit (23 cm inheight from the soil surface). For ‘Evangeline’, four to five main vinesarose from the main stem near the soil surface. The stem giving rise tothese vines was 2.5 cm in diameter; the 4-5 lateral vines were 120 cm inlength with diameters of about 0.6 cm at 65 cm from the base, diametersof about 0.7 cm at the base of the vine, and diameters of about 0.46 cmat the first internode of the first fully developed leaf from the apex.Three to four lateral branches arose from each of the main vines. At thefirst internode from the apex, the internode length was about 4.4 cmbetween the first and second fully developed leaves. Internode lengthsfor other sections of the vine averaged about 4.6 cm. Unfolded immatureleaves were dark purple [5R (red) P (purple) (3/2)] for the upper andlower surface, which changed gradually over one to two nodes from theapex to dark green upper surface [7.5 G (green) Y (yellow) (4/4)] togreen lower surface [5 G (green) Y (yellow) (4/4)]. Mature leaves atfive nodes from the apex had an acute apex and mostly a cordate base anda smooth leaf margin. Mature leaves were about 10.4 cm long and 10.9 cmwide. Abaxial and adaxial veins were green [5 G (green) Y (yellow)(4/4)]. The petiole was red [5R (red) (4/6)] at its junction with theleaf, which quickly changed to green [2.5 G (green) Y (yellow) (5/6),and then remained green at the nodal junction. The petiole was 9-10 cmlong at five nodes from the apex, and 3-4 mm in diameter at 5 cm fromthe leafjunction. The dormant nodal meristem also was green [2.5 G(green) Y (yellow) (5/6)]. Immature leaves of ‘Beauregard’ weresometimes dark purple, similar to ‘Evangeline’, but the ‘Beauregard’leaves had zones of green [2.5 G (green) Y (yellow)] on portions of theleaf upper surfaces. The coloration was also more variable on‘Beauregard’ when compared to ‘Evangeline’.

A typical inflorescence of ‘Evangeline’ displayed three flowers perpeduncle. Peduncles were green [2.5 G (green) Y (yellow) (5/6)], about 5cm long, and about 2.3 mm in diameter. Individual flowers were about 3cm long from the base of the calyx. The fused flower petals formed apentagonal pattern with smooth edges. The inner throat of the corollaappeared purple [2.5 R (red) P (purple) (3/6)]. The inner and outerlimbs of the corolla (corollas outermost area, distal from the calyx)were very light purple [5 P (purple) (6/6)]. The five sepals comprisingthe calyx were elliptic with a cordate apex and appeared to be green[2.5 G (green) Y (yellow) (8/4)]; three of these sepals were about 9 mmlong and 3.6 mm wide. Two other sepals (interspersed) were about 2.2 mmwide. Sepal margins were smooth. Stigmata were about 1.7 cm long andappeared to be purple [5 R (red) P (purple) (6/6)]. Five stamens, whichare inferior to stigmata, were attached to the ovary. No fragrance waspresent.

EXAMPLE 1

Tests Conducted

To confirm that ‘Evangeline’ was a new variety, controlled tests (e.g.,pathogen responses and yield) were conducted at the LouisianaAgricultural Experiment Station in Baton Rouge, La. ‘Beauregard’ wasselected for comparison because of its dominance in commercial UnitedStates sweetpotato acreage. Diseases that commonly affect the growth ofsweetpotatoes were selected to test for pathogen responses in bothvarieties. Scions of ‘Evangeline’ and ‘Beauregard’ reacted similarly tomost diseases evaluated in the controlled tests. ‘Evangeline’ and‘Beauregard’ were intermediate to resistance for soil rot caused byStreptomyces ipomoeae (Person & W. J. Martin) Waksman & Henrici.‘Evangeline’ and ‘Beauregard’ showed similar resistance to Fusarium wiltor stem rot caused by Fusarium oxysporum Schlect. f. sp. batatas(Wollenw.) Snyd. & Hans.

Nematode reproduction was measured in greenhouse tests. ‘Evangeline’ washighly resistant to southern root-knot nematode, Meloidogyne incognita(Kofoid & White 1919) Chitwood 1949. ‘Beauregard’ was less resistant tosouthern root-knot nematode. ‘Evangeline’ and ‘Beauregard’ exhibitedsimilar resistance to Fusarium root rot caused by Fusarium solani(Sacc.) Mart. emend. Snyd. & Hans. ‘Evangeline’ and ‘Beauregard’ storageroots both were susceptible to bacterial soft rot caused by Erwiniachrysanthemi Burkholder, McFadden & Dimock. ‘Evangeline’ and‘Beauregard’ both were resistant to Rhizopus soft rot caused by Rhizopusstolonifer (Ehr. ex. Fr.) Lind. Incidences of circular spot caused bySclerotium roltsii Sacc. were similar for ‘Evangeline’ and ‘Beauregard’.

‘Evangeline’ did not appear to show any novel insect resistance. Both‘Evangeline’ and ‘Beauregard’ showed similar levels of susceptibility toinsect pests, for example, banded Cucumber Beetles (Diabrotica balteataLeConte), white grubs (Plectris aliena Chapin or Phyllophaga spp.), andsweetpotato weevils (Cylas formicarius (fab.)).

To determine yield production, complete-block trials using fourreplications of ‘Evangeline’ and ‘Beauregard’ each were conducted at theLouisiana Agricultural Experiment Station Sweet Potato Research Stationin Chase, La. in 2005. ‘Evangeline’ and ‘Beauregard’ sweetpotato plantswere transplanted in randomized complete-block trials at 31 cm spacingsin Gilbert silt loam soil at the Sweet Potato Research Station. Eachblock/plot was fertilized with 250 pounds per acre of a mixed fertilizercomprising 13% N, 13% P₂O₅, and 13% K₂O. ‘Evangeline’ was compared to‘Beauregard’ at early, middle, and late transplanting dates at eachlocation beginning in May-June. Average yields were measured for thefollowing grades of roots: U.S. #1 (51-89 mm in diameter, 76-229 mmlong); Canner (25-51 mm in diameter, 51-178 mm long); and Jumbo (largerthan U.S. #1 in diameter, length or both, and without objectionabledefects). A typical marketable root of ‘Evangeline’ was 140-150 mm long,60-70 mm in diameter, with mostly round-elliptic in shapes. The base ordistal end tended to be more elongated in comparison to slightly rounderapex (proximal end). U.S. #1 roots typically weighed 150-190 g.

The early transplanting date trial was conducted at the Sweet PotatoResearch Station. ‘Evangeline’ and ‘Beauregard’ were transplanted onJun. 9, 2005, and harvested on Sep. 23, 2005 (106 days after planting).Average yields, measured as Metric Tons per Hectare (“MT·ha⁻¹), areshown in Table 2. TABLE 2 Selection US#1^(†) Canners† Jumbos† TMY^(‡†)‘Evangeline’ 21.7a 5.6a 2.8b 30.1a ‘Beauregard’ 19.2a 2.5b 15.0a 36.8aLeast Significant 10.5 2.5 8.3 12.6 Difference LSD (P < 0.05)^(†)Average yields in MT · ha⁻¹ of varieties followed by a common letterdo not differ significantly (P < 0.05) according to Duncan's MultipleRange Test.TMY^(‡)= total marketable yield

A second transplanting date trial was also conducted at the Sweet PotatoResearch Station on Jun. 16, 2005, and harvested on Sep. 23, 2005 (99days after planting). Average yields (MT·ha⁻¹) of ‘Evangeline’ and‘Beauregard’ are shown in Table 3. TABLE 3 Selection US#1† Canners^(†)Jumbos^(†) TMY^(‡†) ‘Evangeline’ 21.0a 6.8a 2.7b 29.9a ‘Beauregard’22.3a 8.2a 6.6a 32.3a Least Significant 6.5 3.1 3.1 5.6 Difference LSD(P < 0.05)^(†)Average yields in MT · ha⁻¹ of varieties followed by a common letterdo not differ significantly (P < 0.05) according to Duncan's MultipleRange Test.TMY^(‡)= total marketable yield

A late transplanting date trial was also conducted at the Sweet PotatoResearch Station on Jul. 11, 2005, and harvested on Oct. 18, 2005 (99days after planting). Average yields (MT·ha⁻¹) by grade are shown inTable 4. TABLE 4 Selection US#1^(†) Canners^(†) Jumbos^(†) TMY^(‡†)‘Evangeline’ 8.4a 8.8a 0.3b 17.5b ‘Beauregard’ 12.1a 6.9a 3.6a 22.5aLeast Significant 4.1 2.3 1.6 4.2 Difference LSD (P < 0.05)^(†)Average yields in MT · ha⁻¹ of varieties followed by a common letterdo not differ significantly (P < 0.05) according to Duncan's MultipleRange Test.TMY^(‡)= total marketable yield

As shown in Tables 2-4, ‘Evangeline’ produced yields comparable to‘Beauregard’ at two early transplanting dates (112% and 94% of‘Beauregard’ for U.S. #1 grade; 82% and 93% of ‘Beauregard’ for totalmarketable yield). At a later planting date, ‘Evangeline’ had yieldsthat were slightly less than those of ‘Beauregard’. Replicated plots atother farms have not shown any predisposition of ‘Evangeline’ to havelow yield for early, middle, or late season plantings. ‘Evangeline’ hadharvestable roots approximately 110-115 days after planting, which istypical development time for sweetpotatoes. There was a tendency for‘Evangeline’ to produce fewer Jumbos in comparison to ‘Beauregard’, butsince this root category is of less economic value, this feature may notbe significant.

Sugar profiles for baked ‘Evangeline’ and ‘Beauregard’ are shown inTable 5. For this test, roots were stored for five months after whichthey were baked at 190° C. for approximately 2.0 h. In a second test,roots were stored for three months and then baked at 190° C. forapproximately 2.0 h. Sucrose content in baked ‘Evangeline’ was nearlytwice that found in baked ‘Beauregard’. In contrast, ‘Beauregard’ hadnearly twice as much maltose as ‘Evangeline’. Total sugar content didnot differ much between ‘Evangeline’ and ‘Beauregard’. However, maltoseis rated to be about 50 percent less sweet than sucrose. Therefore,‘Evangeline’ sweetpotatoes exhibited a greater sugar profile than‘Beauregard’ sweetpotatoes. TABLE 5 Selection Fructose‡ Glucose‡Sucrose‡ Maltose‡ Total sugars^(†‡) ‘Evangeline’ 5.3 (2005) 4.6 (2005)62.5 (2005) 26.5 (2005) +111 98.9 (2005) 5.0 (2006) 5.8 (2006) 64.1(2006) 34.8 (2006) 109.7 (2006) ‘Beauregard’ 6.7 (2005) 8.9 (2005) 36.0(2005) 51.2 (2005) 102.8 (2005) 6.1 (2006) 8.9 (2006) 22.3 (2006) 54.3(2006)  91.6 (2006)^(†)Total sugars = fructose + glucose + maltose + sucrose.^(‡)mg · g⁻¹ fresh weight basis.

‘Evangeline’ should be a valuable commercial sweetpotato variety.‘Evangeline’ produced plants (sprouts) comparable to ‘Beauregard’,although the number of plants per acre was slightly greater for‘Beauregard’. Days to harvest for ‘Evangeline’ were similar to‘Beauregard’. ‘Evangeline’ exhibited superior flesh color and higherdesirable sugar content. ‘Evangeline’ is ideally suited for productionon land infested with southern root-knot nematode and soil rot.

1. A new and distinct variety of Iponoea batatas plant named‘Evangeline’ as described and illustrated in the specification herein.